Optometric Management Tip # 222 - Wednesday, April 19, 2006
Pupil Dilation: A Tip to Improve Patient Flow
Some tips are true gems and this is one of them, in my opinion. One of the biggest factors in
patient flow in an eye care practice is pupil dilation. It’s not that it takes so much time to
instill drops or perform the dilated fundus exam; it’s the inefficiency of having to see each
patient twice. The logistics of moving people in and out of exam rooms and reviewing the details
of each case is time consuming. If you typically see 25 patients per day, but you have to see
most of them twice, it really adds up!
Pre-dilation
In order to speed up patient flow, I’ve tried various attempts at instilling mydriatic drops before
the doctor sees the patient. Most of these efforts have not worked well, because the cycloplegia
that accompanies the mydriasis has adversely affected the accuracy of the refraction. I value clear,
comfortable vision too highly to accept any technique that reduces the accuracy of my spectacle and
contact lens Rx.
A method that I have been using with much success for over 20 years is to have my technician instill
a non-cycloplegic dilating drop during the pretest work-up. I first wrote about this technique in
an article published by Optometric Management in 1989, but it’s still not used much in our profession.
The non-cycloplegic mydriatic
There is really only one commercially available eye drop that dilates the pupil without causing any
effect on accommodation and that is phenylephrine hcl, also known as neosynephrine and other brand
names. This is a fairly weak and slow-acting mydriatic drug, but the fact that it does not induce
any blur and does not change the refractive state of the eye makes it useful in practice.
Phenylephrine comes in 2.5% and 10% concentrations. I use the 2.5% because it has less risk of
systemic side effects.
Standard of care
Let’s be clear that phenylephrine does not produce as much dilation as tropicamide --- and you’ll
still need to add tropicamide when indicated for a full view of the peripheral retina. Phenylephrine
alone is not the standard of care for a dilated fundus exam, but most of us do not dilate every patient
at every exam.
Of course we all dilate lots of patients, and I don’t mean for this topic to lean toward a commentary
on how often one should dilate – I’ll leave that to each doctor’s professional judgment. There are
many protocols out there. Some doctors dilate every patient at every visit; some dilate at the first
exam and then periodically as indicated by history, symptoms and time intervals; and some hardly ever
dilate. It might be said that the standard of care is not really about dilation; but rather about
adequately visualizing the fundus. You should always use your judgment and fully dilate when you need
to.
By having my technician instill the phenylephrine drops before I see the patient, I’m able to obtain a
large enough pupil to use a binocular indirect ophthalmoscope or a 78/90 diopter fundus lens on most
patients. I will still add a drop of tropicamide when needed, but in many cases, with healthy established
patients, the phenylephrine is enough.
Use in practice
The success or failure of this dilation routine is in the little details. Here are some tricks that
I’ve developed over the years.
- Phenylephrine takes at least a half hour to work well and 40 minutes is even better. This is
important to realize. It is slow acting. We instill it as the very first step in our pretesting
protocol.
Our techs do lots of preliminary tests and the doctor examines the fundus as the last
step, so there is usually ample time. You may want to record the time of instillation and keep an
eye on the clock as you begin using this technique.
- We do not check angles or IOP prior to instilling drops, but if you are worried about angles you
could train a tech to do that.
- Our techs always ask three questions before dropping: 1. Are you allergic to any eye drops?
2.
Have you been told you have glaucoma or are a glaucoma suspect? 3. Are you pregnant (appropriate patients only)?
If the answer is yes to any of these, the tech does not pre-dilate and the doctor will decide.
- The tech tells the patient that we are using a mild dilating drop that will not affect vision or driving.
The patient can return to work with no problem.
- We instill two drops of phenylephrine in each eye (both at once) to be sure that we get at least one good
drop in place. Do not use an anesthetic before the drops because that will rough up the epithelium in some
people and will cause problems with refractive tests and acuity.
- You can still check basic pupil response with a slit lamp or BIO light because the mydriasis is not that
strong, but any subtle pupil defects will not be visible. You could train your tech to evaluate pupils before
instilling drops or reappoint to thoroughly check pupils if it is needed.
- Some people respond better to phenylephrine than others, but older folks often respond well.
- If you need a larger pupil, just add a drop of Paremyd or Mydriacyl after your refraction. The head start
with the phenylephrine as well as the cross-action with tropicamide makes the full dilation occur faster than
usual.
I think you’ll like this technique if you try it. I’ve never had a spectacle Rx re-make that was attributed to
phenylephrine. The pupils are not so big that you have trouble doing a contact lens evaluation during the
routine eye exam. A nice bonus is that patients are able to see just fine to select frames and order glasses
after the exam.
I have more tips on pupil dilation and I’ll cover them next week.
Best wishes for continued success,
Neil B. Gailmard, OD, MBA, FAAO
Chief Optometric Editor, Optometric Management